One of the major problems in performing temperature surveys of steam zone observation wells is the poor response time due to heat convection in the water in the well.
Previously, such surveys were performed by lowering a temperature probe and its electronics down the center of the well hole. Because of temperature smearing due to heat convection in the water, a running survey of the well would give a significantly different temperature profile of a well than a stop-and-start survey. For instance, in one survey, when the survey was stopped the temperature rose over 50.degree. F. over what was obtained at the same point from the running survey. Thus it would be advantageous to reduce the temperature smearing due to heat convection in the water.
Another problem associated with such surveys is that the temperatures in the steam zone observation wells can reach 600.degree. F., which can adversely affect on the accuracy of surveys were the electronics are lowered into the well hole. Thus, it would be advantageous to use a system that allows the electronics to remain above ground.